The invention relates to a battery for a vehicle having a plurality of battery cells forming a cell stack. During the operation of the battery, electric power can be drawn from or supplied to the cell stack via at least one cable. The invention further relates to a method for operating such a battery.
Very high heating in high-voltage batteries for vehicles, especially in lithium-ion-based traction batteries, can cause serious malfunctions or can even endanger people. To prevent large local heat generation, detachable junctions of cables inside the battery are carefully constructed. Compliance with maintaining a predetermined tightening torque at screw-connected junctions is strictly adhered to. High quality of cable lugs and plug connections is observed for terminal connections or crimp connections so as to provide a detachable junction with a particularly low electrical resistance. This is to ensure that no local overheating occurs even under harsh operating conditions of the battery, which supplies a high electrical current and high electrical power, over the entire life cycle of the battery. Such overheating may occur for example with a loose junction.
JP 09035753 A describes a circuit arrangement for a battery, wherein a first voltmeter measures a current, which flows through a measuring resistor between two contact pins connected the two battery terminals. A second voltmeter measures the voltage across two additional contact pins which are also coupled with the two battery terminals. The contact resistance of the contact pins can be determined therefrom. Such circuit arrangement voltage for measuring the contact resistance with two voltmeters is very cumbersome.
It is therefore an object of the present invention to provide a battery and a method of the aforementioned type which enables a particularly safe operation of the battery in a simple manner.